Loss Of Firmness Research Articles

Estimating the Physicochemical and Antioxidant Properties of Hardy Kiwi (Actinidia arguta) Treated with 1-Methylcyclopropene during Storage

In fruit storage, new methods are being sought to extend the distribution period while maintaining the highest quality parameters of the fruit, i.e., the physical and chemical characteristics of the fruit, but also the health-promoting properties. One method is to treat the fruit with 1-MCP, which effectively inhibits fruit ripening, since the main reasons for limiting the distribution of minikiwi fruit are rapid ripening and the loss of firmness. It is also highlighted that minikiwi is a source of antioxidants, which, as highly reactive compounds, are quickly degraded during storage. This study evaluates the effectiveness of using 1-MCP to reduce minikiwi softening and maintain the high antioxidant properties of the fruit. In the experiment, minikiwi fruits of the ‘Ananasnaya’ cultivar were used. After harvesting, the fruits were treated with 1-methylcyclopropene at a concentration of 0.65 µL/L. Fruits treated in this way were stored in ordinary cold storage (NA) and under low oxygen concentration (ULO) conditions for a period of 12 weeks. The fruits’ physicochemical properties, sugar and acid contents and antioxidant potential, which consisted of ascorbic acid, polyphenols, phenolic acids, flavonols and flavan-3-ols, were evaluated. The application of 1-MCP is effective in reducing the loss of firmness in the minikiwi during storage, but the blocking of minikiwi ripening by 1-MCP makes the fruit less sweet and more acidic. Fruits treated with 1-MCP had higher antioxidant activity and a higher content of biologically active compounds. The effect of 1-MCP is stronger for flavan-3-ols, but slightly weaker for phenolic acids. Fruits treated with 1-MCP have a higher antioxidant potential than untreated fruit after a long period of storage.

Effects of Hydroxyethyl Cellulose and Sulfated Rice Bran Polysaccharide Coating on Quality Maintenance of Cherry Tomatoes during Cold Storage.

Cherry tomatoes are easily damaged due to their high moisture content. A composite coating was developed to delay deterioration and prolong storage by mixing antibacterial sulfated rice bran polysaccharides (SRBP) and edible hydroxyethyl cellulose (HEC) with film-forming properties. The effects of HEC, HEC-5% SRBP, and HEC-20% SRBP preservative coatings on the maintenance of the quality of cherry tomatoes (LycopersivonesculentumMill., Xiaohuang F2) during cold storage were investigated. The HEC-20% SRBP coating significantly reduced tomato deterioration and weight loss, delayed firmness loss, decreased polyphenol oxidase activity, and increased peroxidase activity. Furthermore, cherry tomatoes treated with HEC-20% SRBP maintained high levels of titratable acid, ascorbic acid, total phenols, and carotenoids. Cherry tomatoes coated with HEC-SRBP also had higher levels of volatile substances and a greater variety of these substances compared to uncoated tomatoes. In conclusion, the HEC-20% SRBP coating effectively delayed deterioration and preserved cherry tomatoes' nutrient and flavor qualities during postharvest cold storage, suggesting it could be a novel food preservation method.

Effect of Mucilage-Based Edible Coating Enriched with Oregano Essential Oil on Postharvest Quality and Sensorial Attributes of Fresh-Cut Loquat

Due to pulp browning, weight loss, firmness loss, and decay, loquat fruits, and even more minimally processed fruits have a very short post-harvest life. The aim of our study was to evaluate the effect of Opuntia ficus-indica mucilage-based edible coating enriched with oregano oil on postharvest quality, microbial growth, and sensorial attributes of fresh-cut cv Martorana loquat fruit during cold storage. Fresh-cut loquat fruits were dipped in the mucilage-based solution enriched with oregano essential oil (MO-EC) and in distilled water used as control (CTR). According to our results, the mucilage-based edible coating enriched with oregano oil significantly improved the postharvest life of minimally processed loquat fruits by preserving quality, nutraceutical value, and sensory aspects. MO-EC had a barrier effect on fresh-cut loquat fruit, reducing weight and firmness losses, inhibiting TSS, TA, ascorbic acid content decrease, and enhancing the antioxidant activity until the end of the cold storage period (11 days at 5 °C). Microbiological analysis revealed that coated loquat fruits were characterized by a cell density of spoilage microorganisms 1 Log cycle lower than control fruits. The mucilage-based coating enriched with OEO positively affects the visual appearance of fresh-cut loquat fruits, at the end of the cold storage period, MO-EC samples did indeed report visual ratings that were five times greater than CTR samples. Our research suggests that applying mucilage-based coating enriched with OEO improves peeled loquat fruit shelf-life and allows the producers to sell products that are usually considered unmarketable (fruit with epicarp with large spot areas) to the market.

Heterologous Overexpression of Apple MdKING1 Promotes Fruit Ripening in Tomato.

Fruit ripening is governed by a complex regulatory network, and ethylene plays an important role in this process. MdKING1 is a γ subunit of SNF1-related protein kinases (SnRKs), but the function was unclear. Here, we characterized the role of MdKING1 during fruit ripening, which can promote fruit ripening through the ethylene pathway. Our findings reveal that MdKING1 has higher expression in early-ripening cultivars than late-ripening during the early stage of apple fruit development, and its transcription level significantly increased during apple fruit ripening. Overexpression of MdKING1 (MdKING1 OE) in tomatoes could promote early ripening of fruits, with the increase in ethylene content and the loss of fruit firmness. Ethylene inhibitor treatment could delay the fruit ripening of both MdKING1 OE and WT fruits. However, MdKING1 OE fruits turned fruit ripe faster, with an increase in carotenoid content compared with WT. In addition, the expression of genes involved in ethylene biosynthesis (SlACO1, SlACS2, and SlACS4), carotenoid biosynthesis (SlPSY1 and SlGgpps2a), and fruit firmness regulation (SlPG2a, SlPL, and SlCEL2) was also increased in the fruits of MdKING1 OE plants. In conclusion, our results suggest that MdKING1 plays a key role in promoting tomato fruit ripening, thus providing a theoretical basis for apple fruit quality improvement by genetic engineering in the future.

Prolonging the shelf-life of atemoya (Annona cherimola × Annona squamosa) using pulsed electric field treatments

This study aimed to investigate the effects of the pulsed electric field (25, 50, and 100 kV/m) on the ripening of atemoya (Annona cherimola × Annona squamosa) and explore the mechanism of delayed ripening. The results showed that the 50 kV/m pulsed electric field (PEF) treatment significantly affected atemoya preservation, inhibited browning for up to 18 days, and reduced firmness loss by 27% to prolong the shelf-life of the treated sample to 30 days. Regarding the mechanisms, the shelf-life extension was consistent with PEF-induced enzyme inactivation. The 50 kV/m PEF treatments inhibited the respiration rate peak from the 15th day to the 18th day and decremented the activities of pectin methylesterase, polygalacturonase, cellulase, and amylase by 17.0%, 36.2%, 32.3%, and 39.0%, respectively. These results suggest that PEF could extend the shelf-life of atemoya and probably other climacteric fruits.

Effect of vibration and broken cold chain on the evolution of cell wall polysaccharides during fruit cucumber (Cucumis sativus L.) shriveling under simulated transportation

The fruits and vegetables often result in shriveling, which can significantly affect the quality in terms of texture, appearance, and saleable weight during transportation and storage. In this study, fruit cucumbers (Cucumis sativus L.) were subjected to vibration followed by storing them under isothermal and non-isothermal conditions (simulated broken cold chain) for 15 days. Water movement, cell wall polysaccharides and degrading enzymes, cell wall structure of cucumbers were determined. The findings revealed that water initially migrated from the inner pericarp of cucumber. Vibration and broken cold chain damaged the fruit cell wall and cell wall polysaccharides, and increased degrading enzymes, which promoted the water movement from the tissues to the exterior, causing severe shriveling of cucumber. Firmness loss accompanied with cucumber shrivel appeared by as early as 6 days of storage after vibration (5.5 Hz), with decrease of 19.88–29.93 %. However, this phenomenon was not observed in the control cucumber until 12 days after storage with firmness of 8.22 N. Therefore, this study shows that simulated transport vibration and broken cold chain could cause intracellular damage in cucumber tissues, which expedites the process of water loss, degradation of cell wall polysaccharides and shriveling process. The study also reveals that precise temperature control and avoiding vibration of transportation in cold chain logistics of cucumbers are important in maintaining the product quality during storage and transport.

Antioxidant effects of phenolic extract from sugarcane straw and mannan extract from brewer's spent yeast on fresh-cut apples.

Fresh-cut fruit are convenient ready-to-eat products increasingly demanded by consumers, but highly susceptible to oxidation. To increase the shelf life of these products, this industry is currently facing the challenge of finding sustainable natural preservatives capable of maintaining fresh-cut fruit quality while meeting consumers expectations regarding health and environmental concerns. In this work, fresh-cut apple slices were treated with two antioxidant extracts derived from industrial by-products, a phenolic rich extract produced from sugarcane straw (PE-SCS) and applied at 15 g L-1 , and a mannan rich extract obtained from brewers' spent yeast (MN-BSY) applied at two concentrations, 1 and 5 g L-1 . The PE-SCS, having a brown color, imparted a brownish hue to the fruit and increased the browning rate during storage, and neither the initial robust antioxidant response (high SOD, CAT, APX and POX activities), prevented oxidation. The fruit treated with MN-BSY extract at 5 g L-1 showed lower color loss rate and higher PPO inhibition while at 1 g L-1 , it showed lower firmness loss rate and lower lipid peroxidation after 6 days of storage. The results showed that the PE-SCS triggers a potent antioxidant response in fresh-cut fruit and despite at 15 g L-1 it imparted a brown color to the fruit, it may have potential for application at lower concentrations. Regarding MN-BSY, it generally decreased oxidative stress, but its effect on quality maintenance was dependent on the concentration and, thus, to conclude about its potential as a fruit preservative more concentrations must be tested. This article is protected by copyright. All rights reserved.

Narrative tone and earnings persistence

This study contributes to the accounting literature on the intersection between earnings quality and the linguistic features of firms’ financial disclosures. Specifically, it examines the relationship between earnings persistence as an attribute of earnings quality and the tone of United Kingdom annual reports. The expectations-adjustment hypothesis suggests that firms with more persistent earnings streams have incentives to signal their superior earnings quality to capital providers by increasing the positive tone of financial disclosures. Consistent with this hypothesis, this study provides evidence of a positive association between the annual report tone and earnings persistence. Additional analysis reveals that this association is less pronounced in technology firms than non-technology firms. Separating the sample into profit firms and loss firms suggests that the tone is positively associated with the persistence of profits but exhibits no association with the persistence of losses. Disaggregating the tone into positive and negative components indicates that negative tone has a stronger and more negative association with earnings persistence than positive tone. Further, negative tone is negatively associated with earnings persistence in both profit firms and loss firms. In contrast, positive tone is not associated with earnings persistence in profit firms but is negatively associated with earnings persistence in loss firms.

The Changing Role of Accrual Accounting: International Evidence

ABSTRACTUnder the accrual accounting model, the timing role of accruals leads to a negative correlation between accruals and cash flows. Our study investigates the time-series trend of the timing role of accruals and finds a temporal decline in the magnitude of the correlation between accruals and cash flows in our sample of 51 countries over 1991–2019. This decline is primarily caused by increases in loss firms and operation volatility. Several accounting and economic factors, such as the use of accrual accounting, discretionary accruals, matching between revenues and expenses, IFRS adoption, and accounting connectedness, are positively associated with the strength of the accrual-cash flow relation and therefore decelerate the decline of the accrual timing role. Additional analysis suggests that the decline in accrual timing over time is present regardless of a country’s economic growth, legal tradition or institutions, and the extent of the use of accrual accounting.JEL Classifications: M41.

Exploring the potential of alternative current electric field treatment for preservation and the tissue softening mechanism in Pleurotus ostreatus

Pleurotus ostreatus (P. ostreatus) is one of the common edible fungi; however, enzyme reactions during the storage period destroys its texture, resulting in a short shelf life (<10 days) and eventually resulting in wastes. Previous studies have demonstrated that the application of high electrostatic field treatment effectively suppresses the browning of P. ostreatus during storage by inhibiting oxidase activity. In the present study, P. ostreatus was employed as a model to explore cell wall decomposition alleviation by treatment with direct current electric field (DCEF) and alternative current electric field (ACEF). The results indicated that ACEF (400 kV m−1, 90–120 min) led to lower weight loss, lower firmness loss (400 kV m−1, 120 min), and reduced moisture migration during storage. Further research confirmed that ACEF (600 kV m−1, 120 min) treatment inhibited chitinase and β-1,3-glucanase activities by 72% ± 6% and 53% ± 3%, respectively, thereby delaying the disintegration of P. ostreatus during storage. In addition, as a noncompetitive inhibitor, ACEF reduced the Km and Vmax of chitinase and β-1,3-glucanase in P. ostreatus. In conclusion, ACEF treatment significantly alleviated texture loss in P. ostreatus, with a preservation rate of 9.3% ± 0.3%. These findings highlight the potential of ACEF treatment as a promising strategy for enhancing the preservation and commercialization of edible fungi.

Disinfection of Clostridioides difficile on spinach with epigallocatechin-based antimicrobial solutions and sodium hypochlorite

The removal of C. difficile inoculated on fresh spinach leaves washed with antimicrobial solutions was investigated. In addition, the effect of washing solutions on the total aerobic mesophilic bacteria (TAMB) and Enterobacteriaceae in the fresh spinach was examined. The fresh spinach was washed through immersion in different concentrations (MIC, 2xMIC, and 4xMIC) of the natural disinfectant solution (NDS) consisting of EDTA, borax, and epigallocatechin gallate (EGCG) content developed in our laboratory and green tea extract-acetic acid (GTE-AA) for varying contact times (5 and 15 min). Different concentrations (50, 100, and 200 ppm) of sodium hypochlorite (NaOCl) and tap water as the control group were used to compare the effectiveness of the NDS. In addition, the effects of washing on the color, texture, and total phenol content of the spinach were determined. No statistical difference was observed in the washing of the spinach leaves with NDS prepared at 2xMIC and 4xMIC concentrations, while inhibition of C. difficile ranged between 2.11 and 2.32 logs. The highest inhibition was observed in the application of 50 ppm NaOCl for 15 min with a decrease of 2.88 logs in C. difficile spores. The GTE-AA and NDS decreased the number of TAMB by 2.27–3.08 log and, 3.21–3.66 log, respectively. Washing spinach leaves with natural disinfectant for 5 min caused a decrease of 2.58 logs in Enterobacteriaceae load, while washing with 50 ppm NaOCl for 15 min reduced Enterobacteriaceae load by 4 logs. Tap water was ineffective in reducing any microbial load. No difference was detected in the color parameters of the spinach through all washes. Although all antimicrobial washes made a difference in the texture of the spinach, the greatest loss in firmness was observed in the spinach washed with NaOCl. Washing spinach with epigallocatechin-based wash solutions can remove C. difficile in possible C. difficile contamination, thereby reducing the environmental load of C. difficile. Epigallocatechin-based disinfectants can be an alternative to chlorine-based disinfectants in improving the microbial quality of vegetables.

Response of different cultivation substrates on the chilling injury symptom of sweet pepper grown in hydroponics

This study determined the chilling injury interactions of sweet peppers with their hydroponic growth substrate. The treatments were cocopeat, perlite, and a mixture of 50:50 cocopeat and perlite (coco-perlite). The fruits, when harvested, were stored for 50 days using the modified atmosphere package (MAP) at 5 °C. The results revealed no significant interactions between the growth substrate and the chilling injury indicators (respiration and ethylene production rates, electrolyte leakage, malondialdehyde), even though a significant interaction existed with the chilling injury index (a water-soaked area). This is believed to be due to the growth substrate’s significant interactions with soluble solids and dry matter, which aided cellular balance and increased chilling injury tolerance in perlite and coco-perlite treatment. Weight loss rate and firmness loss were insignificant in all treatments, and cocopeat treatment may be considered the worst of all treatments.

Maduración y calidad de mango ‘Manila’ de cosecha temprana tratado con 1-MCP y Ethephon

Introduction: Mango is commercially important; however, its shelf life is short, mainly early harvested mangoes from forced production systems. Objective: The aim of this study was to evaluate the effect of 1-MCP and Ethephon treatments on the ripening stage and quality of early-produced mango fruit. Methodology: Three treatments (control, Ethephon and 1-MCP) were studied, determining respiration rate, weight loss, external color changes (lightness and hue angle), and the contents of carotenoids, ascorbic acid, total soluble solids (TSS) and citric acid. Results: Changes in respiration, color, loss of firmness and ascorbic acid were observed in Ethephontreated fruits in a shorter time, although their carotenoid and TSS content was higher at eating maturity. Fruits treated with 1-MCP had lower respiration and firmness loss, but weight loss was higher, and their external color was not the typical yellow. Limitations of the study: Time and quantity of Ethephon and 1-MCP to improve mango maturation should be evaluated. Originality: The information provided is significant to favor homogeneous mango maturation, as well as an alternative to delay its maturation. Conclusions: The use of 1-MCP helps to delay mango maturation; weight and color losses were lower than expected with this treatment. Fruit maturation of Ethephon-treated fruits was homogeneous, but their shelf life was shorter

The ex-vessel market for tropical tuna in Manta, Ecuador. A new key player on the global tuna market

This paper examines the Manta (Ecuador) market for landings and imports of skipjack, bigeye, and yellowfin tunas through estimation of an inverse almost ideal demand system. Skipjack landings and imports dominate the market. Manta tuna market prices show inflexible price responsiveness to changes in quantities of own species for all imports and landings except yellowfin imports. Simultaneously reducing landings and imports of all species increase vessel profits but is more than countered by economic welfare loss of supply chain firms, exporters, and consumers for a net decline in Ecuador’s economic welfare. Results show two distinct but linked market segments: (1) one well integrated by price with mutually substitutable skipjack imports and skipjack, yellowfin, and bigeye landings and dependent on skipjack imports, and (2) a niche segment centered around yellowfin imports for processors. If the Bangkok market still retains primary global price leadership, it also responds to the growing Manta market.

Effect of Marine-Derived Saccharides on Human Skin Fibroblasts and Dermal Papilla Cells.

The skin is the largest organ of the human body, composed of a diverse range of cell types, non-cellular components, and an extracellular matrix. With aging, molecules that are part of the extracellular matrix undergo qualitative and quantitative changes and the effects, such as a loss of skin firmness or wrinkles, can be visible. The changes caused by the aging process do not only affect the surface of the skin, but also extend to skin appendages such as hair follicles. In the present study, the ability of marine-derived saccharides, L-fucose and chondroitin sulphate disaccharide, to support skin and hair health and minimize the effects of intrinsic and extrinsic aging was investigated. The potential of the tested samples to prevent adverse changes in the skin and hair through stimulation of natural processes, cellular proliferation, and production of extracellular matrix components collagen, elastin, or glycosaminoglycans was investigated. The tested compounds, L-fucose and chondroitin sulphate disaccharide, supported skin and hair health, especially in terms of anti-aging effects. The obtained results indicate that both ingredients support and promote the proliferation of dermal fibroblasts and dermal papilla cells, provide cells with a supply of sulphated disaccharide GAG building blocks, increase ECM molecule production (collagen and elastin) by HDFa, and support the growth phase of the hair cycle (anagen).

An Empirical Model for Predicting the Fresh Food Quality Changes during Storage.

It is widely recognized that the quality of fruits and vegetables can be altered during transportation and storage. Firmness and loss of weight are the crucial attributes used to evaluate the quality of various fruits, as many other quality attributes are related to these two attributes. These properties are influenced by the surrounding environment and preservation conditions. Limited research has been conducted to accurately predict the quality attributes during transport and storage as a function of storage conditions. In this research, extensive experimental investigations have been conducted on the changes in quality attributes of four fresh apple cultivars (Granny Smith, Royal Gala, Pink Lady, and Red Delicious) during transportation and storage. The study evaluated the weight loss and change in firmness of these apples varieties at different cooling temperatures ranging from 2 °C to 8 °C to assess the impact of storing at these temperatures on the quality attributes. The results indicate that the firmness of each cultivar continuously decreased over time, with the R2 values ranging from 0.9489-0.8691 for red delicious, 0.9871-0.9129 for royal gala, 0.9972-0.9647 for pink lady, and 0.9964-0.9484 for granny smith. The rate of weight loss followed an increasing trend with time, and the high R2 values indicate a strong correlation. The degradation of quality was evident in all four cultivars, with temperature having a significant impact on firmness. The decline in firmness was found to be minimal at 2 °C, but increased as the storage temperature increased. The loss of firmness also varied among the four cultivars. For instance, when stored at 2 °C, the firmness of pink lady decreased from an initial value of 8.69 kg·cm2 to 7.89 kg·cm2 in 48 h, while the firmness of the same cultivar decreased from 7.86 kg·cm2 to 6.81 kg·cm2 after the same duration of storage. Based on the experimental results, a multiple regression quality prediction model was developed as a function of temperature and time. The proposed models were validated using a new set of experimental data. The correlation between the predicted and experimental values was found to be excellent. The linear regression equation yielded an R2 value of 0.9544, indicating a high degree of accuracy. The model can assist stakeholders in the fruit and fresh produce industry in anticipating quality changes at different storage stages based on the storage conditions.

Changes in the firmness and other quality parameters of fresh-cut ‘Maradol’ papaya treated with additives and 1-methylcyclopropene

This study aimed to evaluate the effect of 1-methylcyclopropene (1-MCP) applied as pre-cutting, post-cutting, and double application (before and after cutting) on the changes in the firmness and quality parameters of fresh-cut ripe ‘Maradol’ papaya. Four treatments (T1 T4) were used. T1 (Control treatment): Fresh-cut ‘Maradol’ papaya slices (Control treatment or T1) dipped in 1% CaCl2 for 2 min, then sprayed with 0.1% iso-ascorbic acid and 0.05% sorbic acid. One part of the T1 slices were treated with 1000 nL/L of 1-MCP for 12 h at 10 °C (T2). T3: Fresh-cut papaya slices treated with the same additives from the whole papaya treated 1000 nL/L of 1-MCP for 12 h at 20°C. T4: Fresh-cut papaya with additives treated with 1-MCP before and after cutting. All slices were packed in polypropylene trays with a perforated cover and stored at 4 ºC. T3 and T4 slices exhibited lower firmness loss and decreased activity of pectin methylesterase, polygalacturonase, and beta-galactosidase compared to T1 and T2 slices. Moreover, T3 and T4 slices had low translucency and microbial load, complying with the European Union limit (3 log CFU/g). No significant variations in acidity, pH, and total soluble solids were noted between treatments, but higher color values were obtained in T3 and T4 slices. To the best of our knowledge, this is the first study where the combining effects of additives and 1-MCP application before and after cutting extended the shelf-life of fresh-cut ‘Maradol’ papaya for up to 13 days at 4 °C, twice the duration reported by others. Keywords: Carica papaya, Postharvest, Translucency, Quality, Shelf-life

α-Mannosidase and β-D-N-acetylhexosaminidase outside the wall: partner exoglycosidases involved in fruit ripening process.

Cell wall is a strong and complex net whose function is to provide turgor, pathogens attack protection and to give structural support to the cell. In growing and expanding cells, the cell wall of fruits is changing in space and time, because they are changing according to stage of ripening. Understand which mechanisms to produce significant could help to develop tools to prolong the fruit shelf life. Cell wall proteins (CWPs) with enzymatic activity on cell wall polysaccharides, have been studied widely. Another investigations take place in the study of N-glycosylations of CWPs and enzymes with activity on glycosidic linkages. α-mannosidase (α-Man; EC 3.2.1.24) and β-D-N-acetylhexosaminidase (β-Hex; EC 3.2.1.52), are enzymes with activity on mannose and N-acetylglucosamine sugar presents in proteins as part of N-glycosylations. Experimental evidence indicate that both are closely related to loss of fruit firmness, but in the literature, there is still no review of both enzymes involved fruit ripening. This review provides a complete state-of-the-art of α-Man and β-Hex enzymes related in fruit ripening. Also, we propose a vesicular α-Man (EC 3.2.1.24) name to α-Man involved in N-deglycosylations of CWPs of plants.

The Effects of Combined 1-Methylcyclopropene and Melatonin Treatment on the Quality Characteristics and Active Oxygen Metabolism of Mango Fruit during Storage.

In this study, mango fruit (Tainong No. 1) was treated with either 0.1 mg/L 1-methylcyclopropene (1-MCP) alone or with a combination of 0.1 mg/L 1-MCP and 0.2 mM melatonin (MT). The mango fruit was then stored for 10 days at 25 °C and 85-90% relative humidity. Quality characteristics and the active oxygen metabolism of postharvest mangoes were evaluated every 2 days. Compared to untreated mango fruit, those with the treatments of 1-MCP alone or 1-MCP + MT had a better appearance and higher levels of soluble sugar, ascorbic acid, and titratable acidity. Moreover, these treatments prevented the loss of fruit firmness, successfully delayed the escalation of a* and b* values, and reduced malondialdehyde content and superoxide anion generation rate. After 10 days of storage, mango fruit treated by 1-MCP alone or 1-MCP + MT exhibited increased activities of antioxidant enzymes such as ascorbate peroxidase, catalase, superoxide dismutase, and other peroxidases; nevertheless, the two treatment protocols maintained higher mango total phenolic content only at the later stage of storage. These findings suggest that mango fruit treated with 1-MCP alone or with 1-MCP + MT improves the quality characteristics and antioxidant activities. Moreover, compared to 1-MCP treatment alone, 1-MCP + MT-treated mangoes exhibited higher quality and a stronger regulation of active metabolism during storage.

Abscisic Acid Synthesis and Signaling during the Ripening of Raspberry (Rubus idaeus 'Heritage') Fruit.

The raspberry (Rubus idaeus L.) fruit is characterized by its richness in functional molecules and high nutritional value, but the high rate of fruit softening limits its quality during postharvest. Raspberry drupelets have a particular ripening regulation, depending partially on the effect of ethylene produced from the receptacle. However, the possible role of abscisic acid (ABA) in the modulation of quality parameters during the ripening of raspberry is unclear. This study characterized the fruit quality-associated parameters and hormonal contents during fruit development in two seasons. The quality parameters showed typical changes during ripening: a drastic loss of firmness, increase in soluble solids content, loss of acidity, and turning to a red color from the large green stage to fully ripe fruit in both seasons. A significant increase in the ABA content was observed during the ripening of drupelets and receptacles, with the higher content in the receptacle of ripe and overripe stages compared to the large green stage. Moreover, identification of ABA biosynthesis-(9-cis-epoxycarotenoid dioxygenase/NCED) and ABA receptor-related genes (PYRs-like receptors) showed three genes encoding RiNCEDs and nine genes for RiPYLs. The expression level of these genes increased from the large green stage to the full-ripe stage, specifically characterized by a higher expression of RiNCED1 in the receptacle tissue. This study reports a consistent concomitant increase in the ABA content and the expression of RiNCED1, RiPYL1, and RiPYL8 during the ripening of the raspberry fruit, thus supporting the role for ABA signaling in drupelets.